C21D 1/56
General methods or devices for heat treatment: characterised by the quenching agents
Official title: characterised by the quenching agents
C21D1/56 (General methods or devices for heat treatment: characterised by the quenching agents) appears on 578 US grants and 781 published applications in this corpus.
Search patents in C21D- Granted patents
- 578
- Published applications
- 781
- Assignees
- 432
- Inventors
- 2,056
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 2 | 0 |
| 1978 | 6 | 0 |
| 1979 | 0 | 0 |
| 1980 | 4 | 0 |
| 1981 | 2 | 0 |
| 1982 | 2 | 0 |
| 1983 | 6 | 0 |
| 1984 | 7 | 0 |
| 1985 | 7 | 0 |
| 1986 | 7 | 0 |
| 1987 | 2 | 0 |
| 1988 | 4 | 0 |
| 1989 | 2 | 0 |
| 1990 | 4 | 0 |
| 1991 | 2 | 0 |
| 1992 | 4 | 0 |
| 1993 | 5 | 0 |
| 1994 | 5 | 0 |
| 1995 | 3 | 0 |
| 1996 | 5 | 0 |
| 1997 | 9 | 0 |
| 1998 | 12 | 0 |
| 1999 | 8 | 0 |
| 2000 | 5 | 0 |
| 2001 | 10 | 7 |
| 2002 | 16 | 19 |
| 2003 | 9 | 8 |
| 2004 | 10 | 11 |
| 2005 | 2 | 12 |
| 2006 | 4 | 16 |
| 2007 | 4 | 8 |
| 2008 | 5 | 8 |
| 2009 | 10 | 19 |
| 2010 | 10 | 18 |
| 2011 | 8 | 15 |
| 2012 | 7 | 19 |
| 2013 | 9 | 13 |
| 2014 | 14 | 14 |
| 2015 | 10 | 27 |
| 2016 | 16 | 86 |
| 2017 | 19 | 45 |
| 2018 | 31 | 32 |
| 2019 | 53 | 42 |
| 2020 | 25 | 39 |
| 2021 | 41 | 39 |
| 2022 | 26 | 57 |
| 2023 | 20 | 67 |
| 2024 | 25 | 66 |
| 2025 | 38 | 53 |
| 2026 | 41 | 41 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Housing of an induction hardening tool6 Oct 2026US 12,752,288 B2Aktiebolaget Skf
- Carbide refining method of high-carbon high-alloy steel29 Sep 2026US 12,747,488 B2Shanghai Jiaotong University
- Nb microalloyed high strength high hole expansion steel and production method therefor1 Sep 2026US 12,723,289 B2Baoshan Iron & Steel Co., Ltd.
- Alloy for high-stress gouging abrasion11 Aug 2026US 12,703,903 B2Weir Minerals Australia Ltd.
- Steel plate for pressure vessel with excellent cryogenic toughness, and method of manufacturing same28 Jul 2026US 12,692,573 B2Posco
- Heat treatment methods for multiphase superalloys24 Sep 2026US 2026/0286454 A1General Electric Company
- Austenitic stainless steel containing niobium27 Aug 2026US 2026/0250818 A1Doosan Enerbility Co., Ltd.
- Austenitic stainless steel containing tungsten27 Aug 2026US 2026/0250824 A1Doosan Enerbility Co., Ltd.
- Stainless steel clad plate with excellent shape and preparation method thereof20 Aug 2026US 2026/0241428 A1Institute of Research of Iron and Steel, Jiangsu Province/Sha-Steel, Co. Ltd (Cn)
- Steel for knives20 Aug 2026US 2026/0242886 A1Proterial, Ltd.
Most cited
By later US patents
- Process and apparatus for heat treatment of workpieces by quenching with gases80US 5,630,322 AALD Vacuum Technologies GmbH · 1997
- Integrally bladed rotor airfoil fabrication and repair techniques53US 6,536,110 B2United Technologies Corporation · 2003
- Process for intermediately quenching light-metal castings coming from a solution heat treatment furnance45US 5,788,784 AMercedes-Benz AG · 1998
- Machinable austempered cast iron article having improved machinability, fatigue performance, and resistance to environmental cracking and a method of making the same44US 7,070,666 B2Intermet Corporation · 2006
- Fire extinguishing composition and method43US 4,398,605 AFire Out Enterprises Company, Inc. · 1983